Core supporting and rotating assembly

ABSTRACT

A novel core and a novel core supporting and rotating assembly enable a coil of electrical wire to be wound in turns on the core without the use of conventional core supporting clamps, and, if desired, in a continuous operation not requiring an interruption of the winding operation to relocate the core-supporting means to expose the underlying portions of the core for further wrapping. The toroidal core comprises a toroidal body with a central opening and an end ring secured to the lower end thereof, the end ring having an exposed bearing surface for supporting the body and an exposed toothed driving surface for engagement by a correspondingly toothed external driving element. The core supporting and rotating assembly comprises a support having a ring-shaped core-supporting surface adapted to mate with the bearing surface of the core, a toothed driving element engaging the teeth of the exposed driving surface of the core, and means for controllably moving the driving element, thereby to rotate the core. Where the toothed driving element of the assembly is a rotating gear, the portion of the exposed toothed driving surface of the core engaged at one instant by the toothed driving element is in the next instant made available for winding. The resultant toroidal coil-core combination is characterized by indentations in the lower end of the core extending circumferentially around the axis in at least a plurality of sections of indentations. The indentations are of a size and shape such as to drivingly mate with an external driving element having cooperative indentations and have a cross-sectional extent substantially greater than that of the wire turns received therein.

United States Patent Preston Sept. 2, 1975 CORE SUPPORTING AND ROTATING ASSEMBLY [75] Inventor: Wallace M. Preston, West Springfield, Mass.

[73] Assignee: General Instrument Corporation,

Clifton, NJ.

[22] Filed: Nov. 9, 1973 [21] Appl. No.: 414,189

[52] U.S. Cl. 242/4 C; 336/15 [51] Int. Cl. H01F 41/08; H01F 21/02; B65 H 81/02 [58] Field of Search 242/4 R, 4 A, 4 B, 4 BE, 242/4 C; 336/15; 335/213, 210; 269/296 56 References Cited UNITED STATES PATENTS 3,030,038 4/1962 Baker et al. 242/4 A 3,125,307 3/1964 Buralli 3,446,446 5/1969 De Bruin 242/4 C 3,559,899 2/1971 Fahrbach 242/4 B 3,601,731 8/1971 Christiana 335/210 Primary ExaminerBilly S. Taylor [57] ABSTRACT A novel core and a novel core supporting and rotating assembly enable a coil of electrical wire to be wound in turns on the core without the use of conventional core supporting clamps, and, if desired, in a continuous operation not requiring an interruption of the winding operation to relocate the core-supporting means to expose the underlying portions of the core for further wrapping. The toroidal core comprises a toroidal body with a central opening and an end ring secured to the lower end thereof, the end ring having an exposed bearing surface for supporting the body and an exposed toothed driving surface for engagement by a correspondingly toothed external driving element. The core supporting and rotating assembly comprises a support having a ring-shaped coresupporting surface adapted to mate with the bearing surface of the core, a toothed driving element engaging the teeth of the exposed driving surface of the core, and means for controllably moving the driving element, thereby to rotate the core. Where the toothed driving element of the assembly is a rotating gear, the portion of the exposed toothed driving surface of the core engaged at one instant by the toothed driving element is in the next instant made available for winding. The resultant toroidal coil-core combination is characterized by indentations in the lower end of the core extending circumferentially around the axis in at least a plurality of sections of indentations. The indentations are of a size and shape such as to drivingly mate with an external driving element having cooperative indentations and have a cross-sectional extent substantially greater than that of the wire turns received therein.

13 Claims, 9 Drawing Figures 11111 n v Z] T if T 3 u Q 1 J 3 PATENTEB 2975 3 902,674

SEIKET 3 BF 3 CORE SUPPORTING AND ROTATING ASSEMBLY BACKGROUND OF THE INVENTION Winding machines for the semi-automatic wrapping of a wire coil upon an annular toroidal core commonly consist of a shuttle and a core supporting and rotating assembly. Typically, various segment clamps" sup portively and rotatively connect sections of the peripheral circumference of the core to the supporting and rotating assembly. The shuttle is a ring-shaped bobbin, connected to a wire conductor supply spool or initially loaded with a quantity of wire conductor drawn from the supply spool, and is oscillated in a direction substantially parallel to the axis of the core so that the wire is deposited in turn along the inner and outer surfaces of the closed toroidal core. The distribution of the turns depends upon a continuous or step-by-step movement of the core about its axis relative to the position of the wire drawn from the shuttle. Even when a full 360 winding of the core circumference is not required, the clamping and unclamping steps at the beginning and end of the wrapping operation are both slow and, at times, injurious to the core structure.

When it is necessary to wind the core a full 360 about its circumference, the segment clamps invariably intersect the shuttle orbit. Accordingly, in such cases the winding operation is generally stopped at some point prior to such intersection, the clamps opened, the core relocated (rotated) so that an already wound portion of the circumference is adjacent the clamps, the clamps reclosed, and the winding operation then continued. Such an intermediate manual operation is inconsistent with the desirably automatic nature of the wrapping process, requires expensive manpower, and is perforce a time-consuming and critical step of the process.

Accordingly, it is an object of the present invention to provide a fully automatic winding technique utilizing a novel core and a novel supporting and rotating assembly which permits winding of a coil in turns upon the core without requiring the use of any segment clamps.

It is another object to provide such a core and assembly which permits the coil to be wound automatically over the entire circumference of the core without any intermediate clamping or other manual operation.

It is also an object to provide a toroidal coil-core combination wherein the coil is fully automatically wound over up to and including a full 360 of the core without any intervening manual operation.

SUMMARY OF THE INVENTION It has now been found that the above and related objects are attained using a toroidal core having a toroidal body and an end ring secured to the lower end thereof, the end ring having an exposed bearing surface for supporting the body and an exposed toothed driving surface for engagement by a correspondingly toothed external driving element. The bearing surface generally includes a downwardly facing supporting surface and a radially facing aligning surface. The toothed driving surface may be either downwardly facing or radially facing.

The core supporting and rotating assembly utilized in the winding operation comprises a support having a ring-shaped core-supporting surface adapted to mate with the bearing surface of the core, a toothed driving element engaging the teeth of the exposed toothed driving surface of the core, and means for controllably moving the driving element, thereby to rotate the core. Preferably, the core-supporting surface is formed of material having a minimal coefficient of friction and comprises an upwardly facing supporting surface and a radially facing aligning surface. The driving element is configured and dimensioned to be received at least in part inside a radially facing aligning surface defined by a vertical projection of the inner periphery of the supporting surface.

In one embodiment, the driving clement comprises an arm having teeth on an extremity thereof engaging the core teeth, the arm being rotatable about an axis substantially coincident with that of the core, thereby to cause the core to rotate with the arm. In an alternative embodiment, the driving element comprises a gear meshing with the core teeth, the gear being rotated by the moving means, thereby to cause the core to rotate in a corresponding manner. The gear may be provided either with axially upwardly extending teeth to mesh with axially downwardly extending core teeth, or with radially extending teeth to mesh with radially extending core teeth.

The toroidal coil-core combination comprises a toroidal body having upper and lower ends and a central opening, and a coil comprising turns of wire wound through the central opening and around the body. Indentations in the body at the lower end thereof extend circumferentially around the axis of the core in at least a plurality of sections of indentations, the indentations being of a size and shape such as to drivingly mate with an external driving element having cooperating indentations thereon.

In one embodiment, the coils extend circumferentially over one or more circumferential portions of the core, and the sections of indentations are located at other circumferential portions of the body. In an alternative embodiment, the sections of indentations extend completely around the axis of the body, the wire turns being received in at least some of the indentations and preferably in substantially all of them. In any case, the indentations have a cross-sectional extent substantially greater than that of the wire turns received therein, the indentations being adapted to function as gear teeth mating with cooperative gear teeth indentations on the external driving element.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary elevation view, partially in cross-section, of a toroidal core seated on a core supporting and rotating assembly according to the present invention;

FIG. 2 is a fragmentary planar view of the core taken along the line 22 of FIG. I, with the relative location of one of the shuttle-receiving slots of the support assembly being indicated in phantom line;

FIG. 3 is a planar view of the external driving element taken along the line 33 of FIG. 1;

FIG. 4 is a fragmentary elevation view, partially in cross-section, of a second embodiment of a toroidal core seated on a core supporting and rotating assembly according to the present invention;

FIG. 5 is a fragmentary planar view, partially in crosssection, of the core and a portion of the external element taken along the line 5-5 of FIG. 4;

FIG. 6 is a planar view, partially in cross-section, of a portion of the external driving element taken along the line 66 of FIG. 4;

FIG. 7 is a fragmentary elevation view, partially in cross-section, of a third embodiment of a toroidal core seated on a core supporting and rotating assembly of the present invention;

FIG. 8 is a planar view, partially in cross-section, of the core and a portion of the external driving element taken along the line 88 of FIG. 7; and

FIG. 9 is a planar view, partially in cross-section, of a portion of the external driving element taken along the line 9--9 of FIG. 7.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing and in particular to FIGS. 1-3 thereof, therein illustrated is a toroidal core generally designated by the numeral 10 comprising a toroidal body I2 having an upper end 14, a lower end 16, and a central opening 18 therethrough. The body 12 is generally fabricated from any magnetic material such as the ferromagnetic materials of suitable dielectric and permeability characteristics for transformer use, and has the configuration of an annular frustrum of the type frequently utilized in cathode ray tube magnetic deflection yokes (the upper end 14 being the rear of the yoke and the lower end 16 being the front). An end ring generally designated by the numeral 20 is secured to the lower end 16 of the core body 12 for rotation therewith, and has an exposed bearing surface generally designated by the numeral 22 for supporting the core body 12 and an exposed downwardly facing toothed driving surface generally designated by the numeral 24 for engagement by a correspondingly toothed upwardly facing external driving element. Another end ring 32 is typically located at the upper end 14 of the core body 12, both end rings 20, 32 being formed of electrically insulating material and preferably provided with a plurality of axially and/or radially exposed grooves (not shown) to facilitate the receipt and retention of winding turns in predetermined locations. The end rings 20, 32 are typically formed of insulating plastic and may be either independently fabricated or molded in situ as described in Gostyn et al. application U.S. Ser. No. 414,978, filed Nov. 12, I973.

In the lower end ring 20, the exposed bearing surface generally designated by the numeral 22 has a downwardly facing supporting surface 34 and preferably also a radially facing aligning surface 36. The exposed toothed driving surface generally designated by the numeral 24 is downwardly facing and provided with four sections of indentations 38 defining core teeth 40 along the lower circumferential portion of the end ring 20.

The core supporting and rotating assembly generally designated by the numeral comprises a stationary support 5], a movable toothed driving element generally designated by the numeral 52, and means 53 for controllably moving the driving element 52. The stationary support 51 has an upwardly facing ring-shaped core-supporting surface generally designated by the numeral 54, which in turn has an upwardly facing supporting surface 55 adapted to mate with the downwardly facing supporting surface 34 of the end ring bearing surface 22, and preferably also has a radially facing aligning surface 56 adapted to mate with the aligning surface 36 of the end ring bearing surface 22.

Surfaces 55 and 56 of the core-supporting surface 54 are desirably formed of material with a minimal coefficient of friction, such as tetrafluoroethylene, to promote non-binding slippage between the rotating core 10 and the stationary support 51. A plurality of circumferential slots or openings A in the support 51 permit passage of the shuttle therethrough during the wrapping process.

The toothed driving element 52 in this embodiment comprises a pair of outwardly rotatable arms 57, each having teeth 58 on an extremity thereof engaging the teeth 40 of the core 10 (and, more particularly, of the lower end ring 20). The core teeth 40 of the exposed toothed driving surface 24 of the lower end ring 20 are downwardly extending, and the assembly teeth 58 at the ends of arms 57 of the toothed driving element 30 are upwardly extending, so that when the core 10 is properly positioned on the assembly 50 there is a gravity-induced physical interlock between the assembly teeth 58 and the core teeth 40 to cause the core 10 to rotate with the arms 57. The driving element 52 is mounted on means for controllably moving it, such as the drive shaft 53 of a conventional stepping motor 62 providing a continuous or programmed step-by-step rotational motion. The stepping motor 62 is adapted to rotate the arms 57 about an axis substantially coincident with that of the core 10, rotation of the arms 57 in turn causing rotation of the core 10 by means of engagement between the core teeth 40 and assembly teeth 58.

Obviously the sections of the indentations 38 (and core teeth 40) of the exposed toothed driving surface 24 are preferably situated in areas of the ring circumference which are not to be wound with conductor to eliminate the need for intermediate repositioning of the core 10 on the support assembly 50. When a full 360 circumference of the core 10 must be wound, however, a plurality of pairs of sections of indentations 38 are provided on the driving surface 24. Accordingly, intermediate repositioning of the core 10 on the support assembly 50 is easily accomplished in a minimum of time, without any section clamping operations, by merely raising the core 10 to break the interlock between the element 52 and the first pair of sections of indentations 38, rotating the core element 52 and lowering the core 10 to interlock the element 52 with another pair of sections of indentations 38, the first pair of sections now being available for winding.

In a preferred embodiment the sections of indentations 38 extend on the ring circumference completely about the core axis and the indentations 38 have a cross sectional extent substantially greater than the wire turns to be received therein. Thus at least some of the indentations 38 serve both as receivers for the wire turns and as gear teeth for mating with the cooperating gear teeth 58 of the assembly 50. Naturally in such a case the assembly teeth 58 and the core teeth 40 must be cooperatively designed to insure that the assembly teeth 58 do not injure wire turns received in the indentations 38 when the teeth 58 are engaging the teeth 40 defining such indentations 38, and, coversely, that the wire turns in indentations 38 do not interfere with the engagement of core teeth 40 with assembly teeth 58.

To facilitate positioning of the core 10 on the assembly 50 and continuous engagement of the assembly teeth 58 with the core teeth 40 during the wrapping operation, the supporting surface 34 of the lower end ring 20 is stabilized in position atop the supporting surface 55 of the support 51 by means of the abutment between radially facing aligning surfaces 36 and 56, the latter comprising a vertical projection or lip at the inner periphery of the supporting surface 55. The abutment of the inwardly facing radial aligning surface 56 of support 51 against the outwardly facing radial aligning surface 36 of the end ring 20 insures concentricitythat is, that the axis of the core is substantially coincident with the axis about which the arms 57 rotate. Obviously, the length of the arms 57 (including the teeth 58 at the ends thereof) must be such as to permit them to be received at least in part inside the surface 56. The easy drop-in design of the assembly 50 permits rapid and hence economical positioning (and repositioning) of the core 10 thereon.

Referring now to FIGS. 49,-therein illustrated are embodiments permitting winding of a full 360 of the circumference of the core end ring automatically and without manual interruption for repositioning of the core 10 on the core supporting and rotating assembly 50. Referring now in particular to FIGS. 4-6, therein illustrated is a toroidal core 10, similar to that shown in FIGS. l3 except that the exposed toothed driving surface 24 is beveled and extends over the full circumference of the bottom end of lower end ring 20, and a core supporting and rotating assembly 50, similar to that shown in FIGS. 1-3 except that the toothed driving element 52 comprises a plurality of gears and common shafts. The toothed driving element 52 in this instance represents the connection from the shaft 53 of the stepping motor 62 to the driving surface 24 of the core end ring 20. Continuous or step-by-step rotation of shaft 53 is transmitted, through a driving spur gear 72 fitted on shaft 53, to a pair of driven spur gears 74 and a pair of bevel gears 76 connected for rotation therewith by common shafts 77. An intermediate bevel gear 78 journaled in support 51 is driven by each beveled gear 76, and the teeth 79 of intermediate gears 78 act upon the core teeth 40 to cause rotation of the core 10. The exact torques, gear ratios, drive speeds and the like are matters of choice obvious to those skilled in the art. In this fully automatic wrapping or winding system, the rotation of the core 10 results in a change in the engagement between the driving element 52 (as represented by the rotating intermediate bevel gears 78) and the core 10 (as represented by the gear abutting sections of the driving surface 24 of the rotating lower end ring 20). Thus, while at each instant the core circumference portions in the driving area of bevel gears 78 are outside the core circumference portions in which the winding process occurs, the core circumference portions are instant blocked from the winding operation by the abutment thereagainst of the roating bevel gears 78 in the next instant become core circumference portions available for the winding process.

The same effect is obtained in the embodiment illustrated in FIGS. 7-9, where the driving surface 24 of the core 10 is disposed on the inner radial surface of the lower end ring 20 (rather than the bottom end thereof) and the driving element 52" comprises a plurality of gears and common shafts. In this embodiment, the rotation of the stepping motor shaft 53 is transmitted, through a driving spur gear 72 attached to shaft 53, to a pair of driven spur gears 74 and hence to a pair of small spur gears 86 fixed for rotation therewith on common shafts 88. The teeth 90 of the small spur gears 86 mate with the core teeth 40 of the externally toothed driving surface 24 and cause rotation of the core 10 in such a manner that portions of the core circumference at one instant blocked from the winding process by abutment of the rotating small spur gears 86 thereagainst are in the next instant available for winding.

In summary, it is seen that three embodiments have been shown and described in detail. In the first embodiment (FIGS. l3) tooth-bearing rotating arms of the assembly engage toothed segments of the core circumference for rotation therewith. This embodiment permits winding of a core without the use of segment clamps, but does require a manual lift-up/drop-in type of repositioning of the core on the core supporting and rotating assembly when a full 360 circumference of the core is to be wound. The other two embodimensts (FIGS. 49) permit winding of a core about a full 360 of its circumference without either the use of segment clamps or a manual repositioning. In these embodiments, one or more rotating gears of the assembly successively engage and release segments of an exposed toothed driving surface on the core circumference, the exposed toothed driving surface being downwardly facing (FIGS. 46) or inwardly radially facing (FIGS. 7-9). In all embodiments, special aligning surfaces facilitate a drop-in positioning of the core on the assembly and low friction supporting surfaces enable free rotation of the core on the assembly under the influence of the toothed driving element of the assembly.

As will be obvious to those skilled in the art, in order to minimize interference of the toothed driving element 30 with the winding operation, the number of arms 57 will be kept to a minimum (preferably one) and each arm 57 will be of narrow width. For similar reasons, although it is less of a factor in the other embodiments where the entire circumferential surface is ultimately made available for winding as the core 10 is rotated on the assembly 50, it is also desirable that the gears 78 and of the driving elements 52' and 52", respectively, be of sufficiently small dimensions as to minimize interference with the movements of the shuttle.

Thus it is seen that the present invention provides a fully automatic winding technique utilizing a novel core and a novel core supporting and rotating assembly which permits winding of the coil in turns upon the core without requiring the use of any segment clamps, and, in the embodiments described in FIGS. 4 thru 9, permits the coil to be wound automatically over the entire circumference of the core without any intermediate clamping or other manual operation. Now that the preferred embodiments of the present invention have been shown and described in detail, various modifications and improvements thereon will become immediately apparent to those skilled in the art. For example, the embodiment illustrated in FIGS. 79 could be modified to use a core with radially outwardly (rather than inwardly) extending core teeth and an assembly with spur gears disposed adjacent the outer (rather than inner) circumferential surface of the core. Accordingly, the spirit and scope of the present invention is to be considered as defined by not the foregoing disclosure, but only by the appended claims.

I claim:

1. A core supporting and rotating assembly for use with a toroidal core defined by a toroidal body and an end ring secured to one end of said body and having an exposed bearing surface for supporting the core and an exposed toothed driving surface for engagement by a correspondingly toothed driving element for rotating the core, said core supporting and rotating assembly comprising a support having a ring-shaped core supporting surface adapted to mate with the core, a toothed driving element engaging teeth of the exposed toothed driving surface of the core, and means for controllably moving said driving element, thereby to rotate the core.

2. The assembly of claim 1, in which said core supporting surface is formed of material having a minimal coefficient of friction.

3. The assembly of claim 1, in which said driving element comprises an arm having teeth on an extremity thereof engaging the core teeth, said arm being rotatable about an axis substantially coincident with that of the core, thereby to cause the core to rotate with said arm.

4. The assembly of claim 1, in which said driving element comprises a gear meshing with the core teeth, said gear being rotated by said moving means, thereby to cause the core to rotate in a corresponding manner.

5. The assembly of claim 4, in which said gear is provided with axially upwardly extending teeth for engaging axially downwardly extending core teeth.

6. The assembly of claim 4, in which said gear is provided with radially extending teeth for engaging radially extending core teeth.

7. The assembly of claim 1, in which said core supporting surface comprises an upwardly facing supporting surface and airadially facing aligning surface.

8. The assembly of claim 7, in which said core supporting surface is formed of material having a minimal coefficient of friction.

9. The assembly of claim 8, in which said driving element comprises an arm having teeth on an extremity thereof engaging the core teeth, said arm being rotatable about an axis substantially coincident with that of the core, thereby to cause the core to rotate with said arm.

10. The assembly of claim 8, in which said driving element comprises a gear meshing with the core teeth, said gear being rotated by said moving means, thereby to cause the core to rotate in a corresponding manner.

11. The assembly of claim 1, wherein said toothed driving element is configured and dimensioned to be received at least in part inside a vertical projection of the inner periphery of said supporting surface.

12. The assembly of claim 9, wherein said toothed driving element is configured and dimensioned to be received at least in part inside a vertical projection of the inner periphery of said supporting surface.

13. The assembly of claim 10, wherein said toothed driving element is configured and dimensioned to be received at least in part inside a'vertical projection of the inner periphery of saidsupporting surface. 

1. A core supporting and rotating assembly for use with a toroidal core defined by a toroidal body and an end ring secured to one end of said body and having an exposed bearing surface for supporting the core and an exposed toothed driving surface for engagement by a correspondingly toothed driving element for rotating the core, said core supporting and rotating assembly comprising a support having a ring-shaped core supporting surface adapted to mate with the core, a toothed driving element engaging teeth of the exposed toothed driving surface of the core, and means for controllably moving said driving element, thereby to rotate the core.
 2. The assembly of claim 1, in which said core supporting surface is formed of material having a minimal coefficient of friction.
 3. The assembly of claim 1, in which said driving element comprises an arm having teeth on an extremity thereof engaging the core teeth, said arm being rotatable about an axis substantially coincident with that of the core, thereby to cause the core to rotate with said arm.
 4. The assembly of claim 1, in which said driving element comprises a gear meshing with the core teeth, said gear being rotated by said moving means, thereby to cause the core to rotate In a corresponding manner.
 5. The assembly of claim 4, in which said gear is provided with axially upwardly extending teeth for engaging axially downwardly extending core teeth.
 6. The assembly of claim 4, in which said gear is provided with radially extending teeth for engaging radially extending core teeth.
 7. The assembly of claim 1, in which said core supporting surface comprises an upwardly facing supporting surface and a radially facing aligning surface.
 8. The assembly of claim 7, in which said core supporting surface is formed of material having a minimal coefficient of friction.
 9. The assembly of claim 8, in which said driving element comprises an arm having teeth on an extremity thereof engaging the core teeth, said arm being rotatable about an axis substantially coincident with that of the core, thereby to cause the core to rotate with said arm.
 10. The assembly of claim 8, in which said driving element comprises a gear meshing with the core teeth, said gear being rotated by said moving means, thereby to cause the core to rotate in a corresponding manner.
 11. The assembly of claim 1, wherein said toothed driving element is configured and dimensioned to be received at least in part inside a vertical projection of the inner periphery of said supporting surface.
 12. The assembly of claim 9, wherein said toothed driving element is configured and dimensioned to be received at least in part inside a vertical projection of the inner periphery of said supporting surface.
 13. The assembly of claim 10, wherein said toothed driving element is configured and dimensioned to be received at least in part inside a vertical projection of the inner periphery of said supporting surface. 